2004 Jeep Grand Cherokee 4.0L Oil Pressure

by Bob Batzel
(Lake Ariel, PA USA)

Just bought a used Grand Cherokee 4.0L 53,000 mi. Oil pressure gauge dropped to 0 on gauge at traffic light. Returned vehicle to dealer who replaced the sending unit and oil pump - problem came back in 1000mi. Only happens when engine is hot, in drive such as at a traffic light and the idle seems a little rougher and slower than normal when it acts up. Increase to even 700 RPM clears problem.They told me a mechanical gauge shows that it doesn't go below 13psi, but electronic gauge drops to o but back to normal with a slight increase in RPM.

Steve Says,

Thanks for using my website. The most likely cause of your problem is low oil pressure. It sounds like what might be happening is maybe some of your engine bearings are getting worn. Many times when the pressure gauge on your dash reads 0 there actually is some oil pressure. I don't know right off hand what the oil pressure spec. is for your engine but 13 PSI may be too low.

I would take it to another shop just to verify that the pressure is normal.

I hope this has helped.